College and Research Libraries Library Growth and Academic Quality THE LATE FREMONT RIDER's famous ob- servations and conclusions on library growth1 were re-examined in a recent article by H. William Axford in this journal.2 Axford sought to find whether or not the growth of university libraries since 1946 was maintaining the pace Rider found typical for the period be- fore 1940, and whether or not Rider's warning that libraries must double in size every fifteen or twenty years in order that their parent institutions might con- tinue to maintain high academic rating is indeed valid. Axford found that uni- versity libraries, in the period 1946-1960, were not growing at a rate which would permit them to double in size every fifteen years, but at only 78 per cent of this rate. He concluded also that "Rider's emphasis on the relationship between the rate of growth of the university li- brary and the over-all quality of the edu- cational program is still essentially cor- rect."3 An examination, however, of the methods whereby Axford's data were chosen, used, and interpreted, may well lead to different conclusions and further questions. It is regrettable that the study of li- brary size and library growth rates is hampered by deficiencies in the quality of available library size and growth sta- tistics. All libraries do not count their holdings in exactly the same way; neither do counting practices in a given library necessarily remain unchanged through- out its history. Progress in intermural 1 Fre mont Rider , "The Gro.wth of American College and University Libraries-and of Wesleya n's" Abo u t B ooks at th e Oli n Library, W esleyan Univer sity, XI (1 940), 1-11. 2 H. William Axford, " Rider Revi s ited, " CRL , XXIII (196 2 ) , 345-47. a Ibid. , p. 347 . MAY 1963 Bv GEORGE PITERNICK Mr. Piternick is Assistant Director of Li- braries at the University of Washington, Se- attle. and intramural standardization has been and is being made; the benefits of each improvement in standardization can be felt, unfortunately, only in statistics gen- erated subsequent to its adoption. Never- theless, library size statistics, if worth gathering . and publishing, are worth using-the degree to which conclusions may be invalidated by flaws in the data must, however, be always considered. American university libraries whose holdings exceeded one million volumes by June 30, 1960, were used by Axford in his study of the first of Rider 's axioms -that college and university libraries, on the average, double in size about every fifteen -:years. Axford's Table 1 illustrates the growth of each of these libraries in the period 1946-1960, ex- . pressing it as percentage increase during the period. Presumably a percentage in- crease of 100 during the period would constitute doubling. Several facts, how- ever, complicate this simple comparison. For one thing, the interval is fourteen years instead of fifteen as Axford as- sumes. Second, the listed library holdings for 1946 are not internally consistent. Some are taken from the July 1947 issue of College and Research Libr~ries~ others from the 1945 edition of the American Library Directory. The figures in the lat- ter publication could apply to the year 1945 at the latest, and frequently refer to a date two or three years earlier. 223 Third, the "average percentage increase" of 78 per cent, as printed, is an un- weighted arithmetic average of individ- ~al percentages and hence of dubious relevance. Last, several errors in listing and computation are detectable. Table I in this paper offers, in revised form, the growth characteristics of the academic libraries Axford selected for study for the period 1946 to 1960. The holdings data for 1946 have been ra- tionalized; they are taken from the July 1947 issue of College and Research Li- braries, supplemented when necessary by data taken from the Princeton Statistics for College and University Libraries for 1945-1946. For each library, the average annual growth rate has been computed as has its corollary value, the doubling time. Doubling time is here used to represent the period of years necessary for a li- brary's holdings to double at the aver- age annual growth rate for the period studied. Table I also shows the growth characteristics of these libraries during the same number of years (fourteen) immediately preceding the dates of Ax- ford's comparison period. For the period 1946 to 1960, the li- braries under study have grown at wide- ly differing rates. Their mean growth rate during this period has been 20.1 years, which, to be sure, indicates a slow- ing down from Rider's average of fifteen years. However, there has been no per- ceptible slowing down in growth rate for these libraries over the previous pe- riod of fourteen years. Their mean dou- bling time between 1932 and 1946 was 20.7 years. Attention is again invited to the wide variation in individual growth rates. In using this ranking as a gauge of over-all academic quality Axford, in his Table 2, did not rank the institutions ac- cording to the Keniston-Berelson rating as he intended, but instead in alphabeti- cal order within two rank clusters used frequently by Berelson; t